/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.dubbo.rpc.protocol.tri;

import org.apache.dubbo.common.logger.Logger;
import org.apache.dubbo.common.logger.LoggerFactory;
import org.apache.dubbo.common.stream.StreamObserver;

public interface Stream {

    Logger LOGGER = LoggerFactory.getLogger(Stream.class);

    void subscribe(TransportObserver observer);

    TransportObserver asTransportObserver();

    void subscribe(StreamObserver<Object> observer);

    StreamObserver<Object> asStreamObserver();

    void execute(Runnable runnable);

    enum OperationResult {
        OK,
        FAILURE,
        NETWORK_FAIL
    }

    interface OperationHandler {

        /**
         * @param result operation's result
         * @param cause  null if the operation succeed
         */
        void operationDone(OperationResult result, Throwable cause);
    }
}
